Priming mixture



ALLER'ION S. CUSHMAN, OF BRIDESBURG, PENNSYLVANIA.

PRIMING MIXTURE.

No Drawing.

Specification of Letters Patent.

Application filed August 20, 1918.

Patented Dec. 23,1919.

Serial No. 250,722.

(FILED UNDER THE ACT OF MARCH 3, 1883, 22 STAT. L., 625.)

.MAN, lieutenant colonel, ordnance, N. A., a

citizen of the United States, stationed at Frankford Arsenal, Bridesburg,Pa., have invented an Improvement in Priming Mixtures, of which the following is a specification.

The invention described herein may be used by the Government, or any of its officers or employees in prosecution of work for the Government, or by any other person in the United States, without payment of any royalty thereon.

My invention relates to an improvement in that class of priming mixtures which are known as non-fulminate or non-mercuric mixtures and whose principal characteristic is in the fact that sulfocyanate of lead or some other element is substituted for the fulminate in mixtures containing potassium chlorate and antimony sulfid. Primers of the sulfocyanate type are well known and have been much used. In order to increase the heat of the chemical reaction which is produced by the functioning of the primer, it has been the custom to introduce a small percentage of some highly inflammable substance in addition to the three principal ingredients referred to, namely: lead sulfocyanate, antimony, sulfid, and potassium chlorate.

Some primer manufacturers have preferred to use for this purpose trinitrotoluol to the extent of five (5%) per cent. of the primer mixture. Primer mixtures made by mixing together about twenty (20%) per cent. of antimony sulfid, twenty-five (25%) per cent. of lead sulfocyanate, fifty (50%) per cent. of potassium chlorate and five (5%) per cent. of trinitrotoluol have been manufactured in great quantity and have been found to function satisfactorily.

My invention has for an object the novel result of providing in a well known primer mixture the means of controlling at any time the rapidity of'functioning and heat of reaction of the primer ingredients in something the same fashion that a mechanical motorof any type can be speeded up or restrained by the action of a throttle.

In carrying out my invention, I keep to the well known art of mixing together about twenty (20%) per cent. of antimony sulfid, fifty (50%) per cent. potassium chlorate,

twenty-five (25%) per cent. leadsulfocyanate, but I substitute for the five (5%) per cent. of trinitrotoluol (T. N. T.) from three (3%) per cent. to four (at%) per cent. of tetranitromethylanilin, this compound being technically known as tetryl. I also add to the composition from one (1%) per cent. to two (2%) per cent. of lead oxid (litharge) PbO.

My objects in substituting the above ingredients are twofold. First, it enables me to control the heat of the primer reaction when the primer is called upon to function. By increasing the amount of tetranitromethylanilin and decreasing the amount of lead oxid I produce a hotter primer. And second, the lead oxid (litharge) is selected by me for introduction in the primer for providing a slight excess of a basic compound which has the effect of correcting a certain well known tendency on the part of primer mixtures to become acid in the course of time and thereby produce deterioration.

I do not limit myself to exact proportions in my improved priming mixture but refer specifically to the introduction of relatively small quantities of a nitrated fuel body such as tetranitromethylanilin and a non-combustible basic inert substance which serves the double purpose of toning down the inflammability of the mixture and provides a slight excess of a basic compound of a nature insoluble in water, designed to correct any tendency toward acidity due to the action of air or moisture on the primer after it has been manufactured. It is manifest that any other insoluble basic oxid might be substituted for thelead oxid to produce the same results.

As far as the selection of the tetranitromethylanilin is concerned for the fuel ingredient, I am aware that other nitrated bodies, such as trinitrotoluol (T. N. T.) have been specified and used.

I claim the following as my invention:

1. A primer mixture comprising a nitrated fuel body with a variable proportion of a non-combustible basic oxid for the purposes described.

2. A primer mixture comprising about fifty (50%) per cent. potassium chlorate, about twenty per cent. antimony sulfid,

about twenty-five (25%) per cent. lead suland a basic metallic oxid. V r

3. A primer mixture comprising three to 5 four per cent. tetranitrometliylanilin and one to tWo per cent. lead oXid, for the purposes described.

4c- A non-fulminate priming mixture composed of antimony sulfid, lead sulfocyanate and potassium chlorate, together With the addition of relatively small quantities of a nitrated aromatic substitution product and a limited quantity of a basic metallic oXid. ALLERTON S. CUSHMAN. 

